Numerical study of the effect of high-explosive storage facility shape on the azimuthal distribution of blast-wave pressures

Detonation propagation in a confined circular arc configuration of an insensitive high explosive PBX9502 is investigated via numerical simulation in this paper. We introduce a steady detonation wave entering the explosive arc with confinements of stainless steel, and then it undergoes a transition phase and reaches a new steady state with a constant angular speed eventually. The influences of the inner and the outer confinements on the propagating detonation wave as well as the characteristics of the detonation driving zone (DDZ) in the steady state are discussed, respectively. Ignition and Growth (I&G) reaction rate and Jones–Wilkins–Lee (JWL) equations of state for the reactants and the products of PBX9502 are employed in the numerical simulations on the basis of a two-dimensional Eulerian code. The equation of state for stainless steel is in the Grüneisen form with a linear shock speed–particle speed Hugoniot relationship. Our results show that the inner confinement dominates the evolution of the detonation wave and the outer confinement only takes effect in a local region near the outer boundary within a limited initial stage during the transition phase. As for the steady state, the existence of the inner confinement makes the DDZ possess a certain width on the inner boundary. While as to the outer part of the detonation wave, the width of the DDZ decreases until the sonic locus intersects with the detonation front shock, which results in the detachment of the DDZ from the outer boundary and makes the detonation propagation fully independent of the outer confinement.

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BLAST WAVE VISUALIZATION AND DENSITY MEASUREMENT AROUND CYLINDERS IN CROSS FLOW: EXPERIMENTAL AND NUMERICAL STUDY

Journal of Flow Visualization and Image Processing ◽

10.1615/jflowvisimageproc.2017021159 ◽

2016 ◽

Vol 23 (3-4) ◽

pp. 323-344

Author(s):

Daniel Klatt ◽

Friedrich Leopold

Keyword(s):

Blast Wave ◽

Numerical Study ◽

Density Measurement ◽

Cross Flow

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Study of Shield Design for Shock Mitigation

Volume 4: Fluid Structure Interaction, Parts A and B ◽

10.1115/pvp2006-icpvt-11-93213 ◽

2006 ◽

Author(s):

Wing Cheng ◽

Kazuyuki Hokamoto ◽

Shigeru Itoh

Keyword(s):

High Explosive ◽

Numerical Study ◽

Computer Code ◽

Layered Materials ◽

Pressure Level ◽

Shock Mitigation ◽

Mechanical Shocks ◽

Layer Structures ◽

Shield Design ◽

Canister Wall

Detonation of high explosive due to impact of fragments and flyer plates was modeled using hydrodynamic computer code. Included in the model were the warhead consisting of casing and high explosive (which is H-6 in this case). An 80-gram fragment simulated projectile (FSP) was used as the projectile. Flyer plates considered are single- and multi-layer structures. A reactive flow model which is able to capture the initiation, propagation and complete detonation or deflagration of detonation was used to predict the occurrence of complete detonation. Analyses were performed with several impact velocities to obtain the velocity beyond which complete detonation would occur. Shields have been used to mitigate mechanical shocks. It has been well established that shields with multi-layered materials with impedance mismatch would reduce shock levels significantly. A numerical study was conducted to derive an optimum shield design with this concept. The model used encompasses a warhead-canister system. It was assumed that one of the two adjacent warheads would detonate. The canister wall was made of multi-layered materials consisting of layers of materials made of metal and lucite. This material combination represents a medium degree of mismatch while still exhibiting certain amount of strength. The model determines the pressure level at explosive in the neighboring warhead. The pressure level was used to determine if detonation would occur, and provided a measure of effectiveness on the shields for shock mitigation.

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Blast Wall Shielding Effectiveness

Volume 4: Fluid-Structure Interaction ◽

10.1115/pvp2017-65187 ◽

2017 ◽

Author(s):

Jihui Geng ◽

J. Kelly Thomas

Keyword(s):

Blast Wave ◽

High Explosive ◽

Blast Loading ◽

Blast Waves ◽

Shielding Effectiveness ◽

Wave Shape ◽

Mitigation Option ◽

Blast Damage ◽

Wave Parameters ◽

Vapor Cloud

Blast walls are frequently considered as a potential mitigation option to reduce the applied blast loading on a building or structure in cases where unacceptably high levels of blast damage are predicted. There are three general explosion types of interest with respect to blast loading: High Explosive (HE), Pressure Vessel Burst (PVB), and Vapor Cloud Explosion (VCE). The blast waves resulting from these explosion types can differ significantly in terms of blast wave shape and duration. The effectiveness of a blast wall depends on these blast wave parameters (shape and duration), as well as the blast wall parameters (e.g., height, width and standoff distance from the protected structure). The effectiveness of a blast wall in terms of mitigating the blast loading on a protected structure depends on the combination of the blast wave and blast wall parameters. However, little guidance is available on the effectiveness of blast walls as a mitigation option for non-HE explosion sources. The purpose of this paper is to characterize the effect of blast wave parameters on the effectiveness of a blast wall and to provide guidance on how to determine whether a blast wall is an effective and practical blast damage mitigation option for a given blast loading.

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